Treatment of textile materials



Patented Feb. 20, 1940 UNITED STATES TREATMENT or TEXTILE nm'ranuns Gustav Widmer, Basel, and wall -mii, mittens.

near

Basel, Switzerland, assignors, by memo assignments, to Cilia Products Corporation, Dover, DeL, a corporation of Delaware No Drawing. Application June 9, 1m. Serial No. 141,384. In Switrerland June! :1. 1m

6 Claims.

This invention consists in a process of treating textile fibers with the aid of condensation products capable of being hardened from aldehydes and aminotriazines. The process may be used for the purpose, among others, of making dressings fast to washing, for example stiffening dressings; furthermore, particularly with the co-operation of suitable additions, for instance softening agents or water-proofing agents, there may be obtained other impregnation effects, for instance an enhanced resistance to creasing, improved shearing strength, animproved wet tenacity or an improved water-proofing. The process is also useful for fixing stiffening dressings or filling agents so that they are fast to washing.

Processes are known in which textile fabrics are treated with soluble artificial resins capable of being hardened, for instance phenol resins or carbamide resins, for the purpose of producing a dressing fast to washing or for rendering the fabric impermeable or for fixing a dressing or filling agent or for producing non-creasing properties.

The known processes, however, have the disadvantage. that for fixing the artificial resin or for fixing the .dressing or filling agent by means of the artificial resin a separate hardening operation-is necessary in which the hardening is accelerated on the one hand by a temperature of substantially above 100 C. and on the other hand by a hardening catalyst, especially one of an acid nature which at the temperature which has to be used is always liable to damage the fiber.

In the copending application Ser. No. 68,355 there is described the use of such condensation products for improving textiles, especially for dressing and for diminishing the tendency to creasing. The process described, however, corresponds in so far with that generally used in the case of the resins capable of being hardened, such as the urea resins and phenol resins, as the process of said specification also requires a heat treatment of the impregnated fiber at temperatures substantially above 100 C. for the purpose of hardening the condensation product.

The present invention is based on the observation that condensation products capable of being hardened and derived from aminotriazines and aldehydes are suitable in themselves or with the aid of a dressing or filling agent or some other addition for fixing on the fiber even at substantially lower temperatures and with the usual auxiliary apparatus without a separate hardening operation. For example, a web of fabric which has been treated with a condensationproduct and if necessary an addition may be dried and hardened by passage between rollers heated with low pressure steam, viz.at temperatures of about 100 0., whereas when a high temperature is required for the hardening process (in "the case of urea or phenol formaldehyde condensation products) the operation requires the use of rollers heated by high pressure steam or electrically. Also temperatures between 50 to 60 C. or even lower temperatures as used in the drying chambers produce satisfactory results. Indeed the reaction may be performed even at room temperature.

Especially suitable are condensation products capable of being hardened from aminotriazines and formaldehyde. Among aminotriazines may be named 2:4z6-triamino-1:3:5-triazine (melamine), or deaminated products thereof, for instance melam; also 2-chloro-4z6-diamino-1z3z5- triazine (chloromelamine) 2-oxy-4 fi-diamino- 1:3:5-triazine (ammeline). However, aldehyde condensation products from other aminotriazines may be used with advantage.

When used as impregnating or fixing agents the condensation products are preferably dissolved in acidified water'or an acid. Suitable acids are inorganic acids, such as hydrochloric acid or phosphoric acid and organic acids such as formic acid, acetic acid, lactic acid, tartaric acid. Weakand even volatile acids may also be used which, apart from the fact that the process is conducted at a low temperature, is a great advantage in respect of properties of the fiber. Instead of free acids also acid yielding substances such as for instance ammonium salts, dibromocinnamic acid and so onmay be used. In all these cases either from the beginning or during the drying and/or-hardening step a pH below 'I is produced.

The fiber may alsobe treated with a neutral or alkaline solution of the condensation product, if desired in the presence of the additional material to be fixed, and the fiber thus treated may be then subjected to the action of acid, for instance by passage through an atmosphere con- 1 taining acid.

The triazine formaldehyde condensation product may be used in various stages of condensation for impregnating the material, for example it may be in the stage of condensation in which it is soluble without limit in water or in the stage in which the solubility in water is limited, or in the hydrophobe stage in which solubility in water has disappeared and solubility in acid appears.

The condensation may also be combined with the impregnation by making an impregnating bath of jtriazine, formaldehyde and an acid condensing agent and any desired addition and impregnating the textile fiber with this bath and drying in ordinary manner. Finally, the fiber may alternatively be impregnated with a solution of the triazine, advantageously in the form of a watersoluble salt, if necessary in the presence of an addition, and then after-treated with formaldehyde in the form of vapor. In the last case the whole condensation is effected on the fiber.

The process is applicable in printing, that is to say for producing local effects on fabrics, for instance by imprinting a printing paste containing the condensation product and if desiredan acid and/or other addition, such as a dressing or filling agent, and if necessary in the presence of a thickening agent. Alternatively the fabric may be locally treated with a neutral or alkaline condensation product, this latter being then fixed by acid. So also to a fabric which has been pretreated wlth a neutral or alkaline dressing mixture-containing a condensation product, a dressing or filling agent may be applied, then a fixed acid as the usual thickening and in this manner the local hardening effect produced. In analogous manner the process may be varied in many ways with or without one or other of the aforesaid additions.

It is also possible to obtain calendering effects which differ from those obtainable by means of the known resins in that they are much more easily produced, since the hardening occurs at a lower temperature, so that no separate hardening apparatus is necessary. Moreover, the effects are of good fastness to washing as compared with those produced by the known artificial resins.

Textile fibers which are suitable for treatment "by the invention are native, regenerated and esterified cellulose, for instancecotton, ramie, linen, hemp, sisal, jute, coconut fiber, artificial silk, also wool, silk or the like, whether dyed or undyed.

Stiifening dressings or filling agents for the fixing of which the invention is particularly suitable are, for example, gum arable, tragacanth, carob bean meal, kaolin, tallow or mixtures of these products.

Softening agents useful for the invention are, for'example, fats, such as olive oil, castor oil; glycerine; hydrocarbons, such as paraffin; quaternary ammonium salts which contain an aliphatic residue having more than 8 carbon atoms, for example the trimethylammonium sulfate of monostearyl-para-phenylendiamine.

Water-repelling additions suitable for the invention are, for example, paraffin, wax, resins, aluminium salts, alkaline earth salts, for instance lime soaps, either singly or intermixed with each other.

The following examples illustrate the invention, the 'parts being by weight; parts by volume have the same relation to parts by weight asthe litre has to the kilo:

Example 1 Bleached and mercerized cotton satin is impregnated with a solution which contains in 1000 parts by volume 120 parts by weight of condensation product (obtained by condensing for about ,4; hour 630 parts of 2:4:6-triamino-l:3:5-triazine (melamine) with 1410 parts by volume of partially neutralized formaldehyde of 32 per cent.

strength by volume at about 80 0., then neutralizing the solution, filtering and drying the filtrate) and 50 parts by volume of formic acidof 86 per cent. strength. The fabric is squeezed between pressure rollers until its weight is 200 per cent. of its dry weight. It is then dried in the usual manner, for instance on a tentering frame. No application of heat is necessary for the drying, but for the purpose of accelerating it warm air at 50-60 C. may be used. The feel of. the fabric is stifi'er and fuller than that of the fabric which has not been treated. By washing for V hour at 90 C. with a solution containing 5 parts of soap per 1000 parts by volume, the dressing is not substantially affected.

The fabric treated as above is wetted with difiiculty by water drops. This water-repelling effect is not removed by the soap treatment described above.

The proportion of the condensation product may be so small that no noticeable stiifening is produced. Even with less than 100 grams of condensation product per litre of bath a diminution of the swelling capacity is obtained associated with an increase of fastness to water. In the case of artificial silk there is also obtained an increase of wet tenacity.

. Example 2 12.6 parts of 2:4:6-triamino-l23:5-triazine and 27 parts by volume of neutralized formaldehyde solution of 30 per cent. strength by volume are boiled together for 10 minutes. After cooling the condensation solution is mixed with 1 part of formic acid of 86 per cent. strength and made up to 100 parts byvolume of water. With this solution a cotton fabric is impregnated, then squeezed to 200 per cent. of the dry weight and dried in the usual manner on a tentering frame. By this treatment there is obtained a good stiff finish fast to washing and similar to that described in Example 1.

Example 3- A hydrophobe condensation product is made as follows: 630 parts of 2:4:6-triamino-1z3z5-triazine are condensed at about 80 C. with 1410 parts by volume of neutralized formaldehyde of 32 per cent. strength until a cooled sample shows a precipitate when diluted with half its volume of 1 water. The solution 'is then dried at a low temperature. The dry product forms a solution with about 0.6 part by volume of water, whereas more water produces a precipitate.

A colored cotton fabric is impregnated under the conditions described in Example 1 with an aqueous solution containing 1000 parts by volume 100 parts of the above condensation product and 40 parts of formic acid of. 86 per cent. strength. A fabric dried in the air at room temperature has a strong stiff finish of good fastness to washing.

The stlfiening effect is still greater if the quantity of condensation product and of the formic acid is doubled in the foregoing prescription without changing the other conditions. The fastness to washing of the finish remains the same.

Like effects with even more strongly hydrophobe products are obtained by, for instance, using instead of the condensation product described above still soluble in a little water a product of the same composition which however has been so much further condensed that it has become wholly insoluble in water.

An aqueous solution containing per 1000 parts by volume 100 parts by weight of such a strongly hydrophobic condensation product, 80 parts by this example, strong stiffening effects of remarkable fastness to washing.

Example 4 A cotton fabric, for instance mercerized shot satin, is impregnated with an aqueous solution containing per 1000 parts by volume parts of the condensation product made as described in Example 1, 50 parts by volume of formic acid of 86 per cent. strength, 5 parts of the trimethylammonium sulfate of mono-stearyl-para-pheny1enediamine.

The fabric is pressed between rollers until it is 200 per cent. of its dry weight and then dried on the tentering frame. The drying may be at ordinary temperature but for accelerating it the temperature may be raised to 50-60 C. The fabric has a very good resistance .to creasing, which property is stable to hot soaping.

Example 5 A cotton fabric is impregnated with an aqueous solution containing per 1000 parts by volume 100 parts of the condensation product made as described in Example 1, 50 parts by volume of formic acid of 86 per cent. strength, 50 parts of an emulsion of paraflin of 20 per cent. strength containing glue, for example, as the emulsifier.

The fabric is then squeezed between rollers until its weight is 200 per cent. of the dry weight and dried with the aid of a drying apparatus usual in the textile industry, that is to say on a tentering frame or with the aid of drying cylinders. By this treatment the fabric acquires strong water-repelling and water-proofing properties. After it has been washed with a liquor containing 5 grams of soap per litre at 90 C. for hour the fabric still retains the greater part of its water-proof character.

A similar result is attained by substituting for the pure paramn emulsion an emulsion containing besides the parafiin an aluminium salt, for instance aluminium acetate; also by impregnating with an aluminium salt in combination with the aminotriazine formaldehyde condensation product there is obtained a good waterrepellent effect fast to washing, whereas with the aluminium salt alone the effect is lost on washins.

The use of aminotriazine formaldehyde 'condensation products for making water-proof finishes not only improves the water-proof character of the impregnated fabrics but at the same time produces a full, firm feel. The degree of feel of the fabric may be varied by addition of softening agents.

Example 6 10 parts of the dry condensation product obtained as described in Example 1 are dissolved in a mixture of 90 parts by volume of water and 10 parts by volume of formic acid of 86 percent. strength and this solution is added to a starch paste obtained by boiling a mixture of 80 parts of potato starch with 900 parts by volume of water and subsequently cooling; the whole is thoroughly mixed.

A cotton fabric of medium weight is saturated with this mixture in'a finishing machine, squeezed and then dried on the tentering frame at 22 C. For accelerating the drying air at a temperature of 50-60 C. maybe used.

By this treatment the starch finish is fixed fast to washing. Even after washing 6 times at 90 C. with a solution containing 5 grams of soap and 2 grams of sodium carbonate per litre the finish remains in the fabric in greater part.

That an optimum fixation is produced by merely drying at room temperature may be proved by the following thermal treatment applied subsequently to the drying at 22 0.:

10 minutes at 70 C. or A minute at C. or V minute at C. or

4 minutes at 140 C.

The fabric thus after-treated in no case shows an improvement in the fastness to washing.

A similar result is obtained if, for example, the 10 parts by volume of formic acid of 86.per cent. strength used for dissolving the condensation product are exchanged for 10 parts by volume of concentrated hydrochloric acid or 7.5 parts by volume of formic acid of 86 per cent. strength or 20 parts by volume of acetic acid of 80 per cent.

. strength or 20 parts by volume of lactic acid of 92 per cent. strength or 10 parts of tartaric acid. Moreover, a similar result to that obtained in this example is produced when the 80 parts of potato starch are exchanged for an equal quantity of wheat starch. 7

An excellent fastness to washing of the fixing effect is obtained if the 10 parts of the condensation product made as described in Example 1 are exchanged for an equal quantity of the strongly hydrophobe condensation product described in the last paragraph of Example 3.

Example 7 A solution of 10 parts of the condensation product made as indicated in Example 1 in a mixture of 90 parts by volume of water and 10 parts by volume of formic acid of 86 per cent. strength is thoroughly mixed with a starch paste containing in 900 parts by volume of water, 80 parts of potato starch and parts of kaolin. A fabric is treated with this mixture as described in Example 6. In this case also the drying follows at ordinary temperature. Washing testsshow surprisingly that the filling material, kaolin, and also the stiffening agent itself is not removed after 6 washings conducted as described in Example 6. The intended filling of the fibers of the fabric is clearly notable in the opacity of the fabric to light.

Example 8 A solution of 10 parts of the condensation product made as indicated in Example 1 in a mixture of 90 parts by volume of water and 10 parts by volume of formic acid of 86 per cent. strength is added to a solution of 80 parts of gum arabic in 1000 parts by volume of water. With this solution a cotton fabric printed in color is saturated as described in Example 6. The excess of liquor is squeezed out by rollers and the fabric is then dried at 34 C. on the tentering frame.

The fabric thus treated ,even after many washings shows a full grip and a medium stiffness; the dressing itself is inconspicuous.

Similar results are obtained when in this example 80 parts of gum arabic are exchanged for 70 parts of carob bean flour or 60 parts of tragacanth.

Example 9 7 parts of a condensation product, made by a short boiling of a mixture of 4.7 parts of melam with 11.3 parts :by volume of formaldehyde of 32 per cent. strength by volume, 20 parts by volume of formic acid of 86 per cent. strength and 0.5 part by volume of concentrated sulfuric acid, precipitating the product of the reaction by dilution with water, neutralizing the suspension with caustic soda solution, filtering and drying the residue, are dissolved in parts by volume of formic acid of 86 per cent. strength, and this solution is thoroughly mixed with 700 parts of potato starch paste of 8 per cent. strength.

A fabric saturated with this stiflening has a hard finish fast to water even when dried at the ordinary temperature.

Example 10 10 parts of the condensation product, made by heating a mixture of 14.6 parts of 2-chJoro-4:6- diamino-1:3:5-triazine, 56 parts by volume of formaldehyde of 32 per cent. strength by volume, 24 parts of ethyl alcohol 01' per cent. strength and 1 part by volume-of concentrated sulfuric acid until a clear solution is obtained, then neutralizing and evaporating to dryness in a vacuum, are dissolved in a mixture or. 60 parts by volume of formic acid of 86 per cent. strength and 40 parts by volume of water, and this solution is mixed into a starch paste as described in Example 9. l

The stiifening thus obtained produces effects similar to those indicated in Example 9.

Example 11 10 parts of a condensation product made from 6.35 parts of 2-oxy-4:6-diamino-l:3:5-triazine, 47 parts by volume of formaldehyde of 32 per cent. strength by volume and 2.15 parts by volume of concentrated sulfuric acid by heating them together at the boiling point for about 2 hours, then neutralizing and evaporating the solution obtained, are dissolved in a mixture of 90 parts by volume of formicacid of 86 per cent. strength and 10 parts by volume of water.

This solution is mixed with a starch paste as indicated in Example 9. The mixture gives dressing efiects similar to those described in Example 9.

Instead of the condensation products being used in acid or acidified solution as indicated in the foregoing examples, dry preparations may also be used, for example such as are made by intermixture of equal parts of. the condensation product and a fixed organic acid such as tartaric acid. Mixtures like these are suitable as commercial products in that they dissolve in water and may be used directly for the various purposes described above, either alone or in admixture with the aforesaid additions, as softeners, stifiening agents, waterproofing agents or the like.

What we claim is:

1. Process for treating textile materials with hardenable condensation products obtained from aldehydes and aminotriazines as essential reactants, wherein the textile material is impregnated with the condensation product or its components whereatter the condensation product thus formed or incorporated is insolubllized at temperatures between room temperature and about C.

2. Process for treating textile materials with hardenable condensation products obtained from aldehydes and aminotriazines as essential reactants, wherein the textile material is impregnated with the condensation product or its components whereafter the condensation product thus formed or incorporated is insolubllized at temperatures between room temperature and about 100 C. at a pH below 7.

3. Process for treating textile materials with hardenable condensation products obtained from formaldehyde and 2.4.6-triamino-1.3.5-triazine as essential reactants, wherein the textile material is impregnated with the condensation product or its components whereafter the condensation product thus formed or incorporated is insolubllized at temperatures between room temperature and about 100 C.

4. Process for treating textile materials with hardenable condensation products obtained from formaldehyde and 2.4.6-triamino-1.3.5-triazine as essential reactants, wherein the textile material is impregnated with the condensation product or its components whereafter the condensation product thus formed or incorporated is insolubilized at temperatures between room temperature and about 100 C. at a pH below 7.

5. Process for making stiffening finishes fast to washing by treating textile materials with hardenable condensation products obtained from aldehydes and aminotriazines as essential reactants, wherein the textile material is impregnated with the condensation product or its components in presence of a stiffening agent whereafter the condensation product thus formed or incorporated is insolubilized at temperatures between room temperature and about 100 C.

6. Improved textile materials characterized by 

